In 2012 the current "Guideline on quality, non-clinical and clinical aspects of medicinal products containing genetically modified cells" was adopted and came into effect. The objective of this guideline was to define scientific principles and provides guidance for the development and evaluation of medicinal products containing genetically modified cells. It was targeted for products intended for use in humans and presented for marketing authorisation. The focus of the document was on the quality, safety and efficacy requirements of genetically modified cells developed as medicinal products. The EMA defined: "The scope of this document is on Gene Therapy Medicinal Products that contain genetically modified cells (ref. Directive 2009/120, Annex 1 par. 3.2.1.21). Its focus is on quality, non-clinical and clinical aspects of genetically modified cells. All cases of genetically modified cells intended for use in humans are included, no matter whether the genetic modification has been carried out for clinical indication or not (e.g. for enhanced manufacturing purposes). The genetically modified cells can be of human origin (autologous or allogeneic) or animal origin (xenogeneic cells), either primary or established cell lines. Genetically modified cells of bacterial origin are excluded from the scope of this guideline. In a medicinal product, the genetically modified cells can be presented alone or combined with medical devices. The requirements described in this document are those relating to market authorisation application, but principles may apply to development stages."

The Guideline from 2012 focused on traditional methods for genetic modification based on the use of vectors carrying recombinant nucleic acids. But especially the field of genome editing technologies which allow a simple approach to genetic modification of cells has undergone an increasing scientific progress. Such new technologies, maybe working with different starting materials or manufacturing processes, should be included in such a guideline, too. Therefore, the EMA published a Concept paper on the revision of the Guideline on quality, non-clinical and clinical aspects of medicinal products containing genetically modified cells on 09 August. The document proposes the revision of the existing guideline which will include the current scientific findings and experiences gathered for CAR-T 29 cells and related products as well as recent developments on tools for the genetic modification of cells (namely genome 31 editing technologies). The proposed timetable states that the draft of the revised guideline will be available by Q1 2018, and therefore the concept paper has been released for a 3 months public consultation.